1. Active Beam Spectroscopy in Hot Fusion Plasmas
(Beam Emission Spectroscopy and MSE)
Manfred von Hellermann
FOM Institute for Plasma Physics Rijnhuizen, NL
Seminar-III
Institute for Plasma Physics
Academy of Sciences
Hefei, China
May, 7, 2007
Acknowledgement:
CXRS groups at JET, TEXTOR, Tore Supra , ASDEX-UG and
members of the ITPA expert group on Active Beam Spectroscopy

2. Beam Emission Spectroscopy as tool for absolute calibration
Combination of CXRS and BES:
common line of sight and beam geometry
Beam Emission Spectroscopy as tool for absolute calibration
of CXRS signals
M. von Hellermann

3. First observation of a CXRS D-alpha spectrum on JET 1986
Alain Boileau, PhD Thesis, University of Montreal 1988
M. von Hellermann

4. W.Mandl 1991, first fully modelled Balmer-alpha-CX and beam spectrum
M. von Hellermann

5. Beam Emission Rate vs. collision energy and electron density
c.f. ADAS file ADF312
M. von Hellermann

6. Beam Emission Rate versus collision energy and ion temperature
ADAS file ADF312
M. von Hellermann

7. Beam Emission rate versus collision energy and C+6 concentration
M. von Hellermann

8. deduction of ion densities without absolute calibration
Combination of CXRS
and BES enables
deduction of ion densities without absolute calibration
and measurement of
optical transmission
local concentration measurements reduced to a line ratio measurement
Note: Atomic rates Q depend on energy, electron and ion densities and
temperatures
M. von Hellermann

9. Comparison of beam line-densities derived from beam stopping and
beam emission respectively
M. von Hellermann

10. TEXTOR comparison of beam line-densities from beam stopping
and beam emission respectively
M. von Hellermann

11. Is the deviation between beam-stopping beam
Questions:
Is the deviation between beam-stopping beam
densities and beam-emission deduced beam
densities due to:
Geometry factors, alignment, beam dimensions ?
Errors in beam stopping cross-sections ?
Errors in beam emission rates ?
Do we need to establish further experiments ?
Do we need to review atomic physics ?
M. von Hellermann

12. D-alpha-BES and D-alpha-CXRS Robert Wolf 1993
M. von Hellermann

13. Ratio of Pi-over-Sigma Group in JET MSE spectrum
M. von Hellermann

14. M. von Hellermann

15. M.von Hellermann et al., ITER report December 2003

16. s- s0 s+
p+2
p+3
p+4
p-2
D-alpha-edge
D-alpha-CX
p-3

17. M. von Hellermann

18. MSE ratio p/s for U-ports 2 &3
M. von Hellermann

19. The most accurate data extracted from the beam spectrum
is the Lorentz split representing the total magnetic field as
local measurement.
This offers a promising back-up to pick-up coils and
magnetic field measurements making use of electronic
integrators.
Expected accuracies are better than 0.5%
M. von Hellermann

20. R.C.Wolf, L-G Eriksson, M von Hellermann, R.König, W.Mandl, F.Porcelli
Nuclear Fusion, 33, 1835(1993), JET-P(93)24
M. von Hellermann